API Reference > geometry-core > Topology > ChainMergeContextOptions > primarySortDirection primarySortDirection primarySortDirection: undefined | Vector3d Direction for primary sort. Default is Vector3d.create(0.294234298, 0.72391399, 0.45234328798) this vector should NOT be along a principal x,y,z direction. The internal form will be normalized. Defined in topology/ChainMerge.ts Line 34 Last Updated: 12 June, 2024